Access control systems electronically control the locking and unlocking of doors including those for buildings, office suites, residences, rental units and retail establishments. These systems typically use some type of “credentialing” method such as pressing RFID cards to a reader, inserting magnetic cards into a slot (e.g., in hotel door locks), or entering PIN codes on a keypad to identify people who are allowed to enter. In order to grant access to people for multiple doors in a building or across multiple buildings, the selected credentialing method has to be synchronized with the lock/device at each door. There are three primary types of credentialing systems: wired systems, standalone systems, and standalone door locks. Each of these existing types of credentialing systems create various challenges in terms of expense, ease of installation, ease of use, connectivity, and security. Therefore, a need exists for improved access control systems that remedy these deficiencies.